3a thread class 0.500" thread length flat chamfer head style 24 thread quantity per inch material is heat treated in accordance to mil-h-6686 unf thread series
2a thread class right-hand 0.750" thread length hexagon head style 20 thread quantity per inch do not dupe to nsn 5305-00-021-3668; this nsn is for pearl harbor use only; this is a non-standard unit-of-issue passivate surface treated unc thread series
3a thread class right-hand hexagon head style 32 thread quantity per inch has 2 slots running full length of the threads on both sides of screw for retaining ring unc thread series
3a thread class right-hand 0.480" thread length hexagon head style 32 thread quantity per inch knurled internally thd sleeve .250-28unf-2b; spring-loaded unf thread series
